问题描述
在有关静态类型的最新问题之后，我再次考虑了数组.我一直以为数组元素只是普通的对象，但是现在我想知道:
After a recent question on static typing, I was thinking about arrays again. I always thought that array elements are just ordinary objects, but now I wonder:
数组的元素本身是否是完整的对象，或者它们是不完整的，而唯一的完整对象是数组本身?
Are the elements of an array complete objects in their own right, or are they incomplete, and the only complete object is the array itself?
如果是这种情况，那么(new T[N])[0]的完整对象是什么，它的类型是什么?
If this were the case, then what is the complete object of (new T[N])[0], and what is its type?
如果元素不完整，是否意味着存在无法静态知道其类型的完整对象? (这与基本/衍生业务不同:new Derived 的类型是静态已知的，尽管可能永远不会记录在该表达式之外.)
If the element is incomplete, then does that mean that there are complete objects whose type cannot be known statically? (This is different from base/derived business: the type of new Derived is known statically, though it may never be recorded outside that expression.)
推荐答案
数组元素不是完整的对象. C ++ 11，[对象简介]§2:
An array element is not a complete object. C++11, [intro.object]§2:
至于(new T[N])[0].完整对象是由 new-expression (T的数组)创建的对象.根据[expr.new]§1，我会说它的类型是"T的N个元素的数组":
As for (new T[N])[0]. The complete object is the object created by the new-expression (an array of T). I'd say its type is "array of N elements of T", as per [expr.new]§1:
这是从T[N]构造的 new-type-id .
请注意，在创建数组时， new-expression 返回一个指向该数组初始元素的指针，而不是指向数组本身的指针.这意味着在这种情况下， new-expression 的类型不是其创建的完整对象的类型.换句话说，无法以任何方式访问完整对象的类型.
Note that when creating arrays, a new-expression returns a pointer to the initial element of that array, not to the array itself. Which means that in such case, the type of the new-expression is not the type of the complete object it creates. In other words, the complete object's type cannot be accessed by any means.
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